(19)

(11)

EP 2 257 684 A2

(12)

(88) Date of publication A3: 12.11.2009 (43) Date of publication: 08.12.2010 Bulletin 2010/49 (21) Application number: 09716546.8 (22) Date of filing: 06.03.2009

(51) International Patent Classification (IPC):  E21B 4/14(2006.01) B23B 47/00(2006.01) B25D 9/00(2006.01) (86) International application number: PCT/US2009/036312 (87) International publication number: WO 2009/111690 (11.09.2009 Gazette 2009/37)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR Designated Extension States: AL BA RS (30) Priority: 06.03.2008 US 34472 01.05.2008 US 150908 (71) Applicants: Patterson, William N. Montrose, CO 81402 (US) Patterson, Glenn Montrose, CO 81402 (US)	(72) Inventors: Patterson, William N. Montrose, CO 81402 (US) Patterson, Glenn Montrose, CO 81402 (US) (74) Representative: Durm & Partner  Moltkestrasse 45 76133 Karlsruhe 76133 Karlsruhe (DE)